低周疲劳中结构钢的宏观与细观变形行为

Macro and Meso Deformation Behaviour in Structural Steel during Low Cycle Fatigue

应用显微硬度法研究了低周疲劳过程中退火１６Ｍｎ钢和正火４５钢的表面细观循环塑性状态变化及其硬化、软化行为，并在统计意义上与材料的宏观循环塑件变形规律进行了比较。结果表明，宏观材料的循环塑性响应与细观尺度上材料的循环硬化、软化行为两者在统计意义上是一致的，而后者在空间分布与时间序列上均表现出显著的不均匀性和非同时性特征。

The change of the cyclic mesoplastic surface deformation and the hardening and softening behaviour of annealed 16Mn steel and normalized 45 steel during low cycle fatigue were investigated by using microhardness method and compared with the rules of the cyclic macroplastic deformation of materials.It showed that the cyclic macroplastic responses of materials were in agreement with the mesoplastic deformation in statistical sense,and the latter appeared remarkable inhomogeneity and unsimultaneity in space distribution and in time sequence during fatigue.